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3 years ago

Solve x^2 + 4x + 8 = 0

Mathematics

1 answer:

Mkey [24]3 years ago

8 0

Answer:

x = -2 + 2 i or x = -2 - 2 i

Step-by-step explanation:

Solve for x:

x^2 + 4 x + 8 = 0

Subtract 8 from both sides:

x^2 + 4 x = -8

Add 4 to both sides:

x^2 + 4 x + 4 = -4

Write the left hand side as a square:

(x + 2)^2 = -4

Take the square root of both sides:

x + 2 = 2 i or x + 2 = -2 i

Subtract 2 from both sides:

x = -2 + 2 i or x + 2 = -2 i

Subtract 2 from both sides:

Answer: x = -2 + 2 i or x = -2 - 2 i

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Read 2 more answers

Write down the nth term of the sequence 5, 8, 13, 20, 29

amid [387]

Hello! To find any number in the arithmetic sequence we can use a formula!

It is given by $a_n =a_1+(n-1)d$

The geometric sequence formula goes by $S_n = \frac{a_1(1-r^n)}{1-r}$

So for this we notice that there's a start of 5 and is being added 3 to get 8.

and then each time it is added by 2 more to get the next time

5
5+ 3 = 8
8 + 5 = 13
13 + 7 = 20
20 + 9 = 29
29 + 11 = 41
41 + 13 = 54
54 + 15 = 69
69 + 17 = 83

Your formula is $a_n = (n-1)^2 + 4

$
Where n starts at 2 not 1

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3 years ago

1. Solve the equations below.

Sergio039 [100]

Step-by-step explanation:

A) 3x + 8 = 23

3x = 23 - 8

3x = 15

x = 15 / 3 = 5

B) 5x + 1 = 3x + 17

5x - 3x = 17 - 1

2x = 16

x = 16 /2 = 8

C) 4 (x+2) = 32

4x + 8 = 32

4x = 32 - 8

4x = 24

x = 24 / 4 = 6

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3 years ago

A right triangle has a hypotenuse of 15 cm. What are possible lengths for the two legs of the

saw5 [17]

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Step-by-step explanation:

you can multiply 5x3 to get 15

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